Testing for marijuana does not provide accurate data with respect to when it was consumed. It could have been a factor in the crash, or it could have been consu

Testing for marijuana does not provide accurate data with respect to when it was consumed. It could have been a factor in the crash, or it could have been consumed days to weeks in the past, as the study author states: “Our testing methods for cannabis remain suboptimal and individuals can test positive for cannabis weeks after they have consumed it.”